Nvidia has touted its Tegra chip for mobile web devices in the past year, but it said today that the chip has more momentum than it previously described.

42 different devices are being designed with the Tegra chip. Customers include 27 different manufacturers as well as 27 different mobile phone carriers around the world. The devices include media players, web pads, and 12 smart phones. Some of them are more like a cross between a phone and a laptop, in a category called mobile Internet devices. That’s more progress than the company reported just a couple of weeks ago.

Mike Rayfield, (pictured) general manager of Nvidia’s mobile business unit, delivered the update during the company’s analyst meeting today at Nvidia’s headquarters in Santa Clara, Calif. The new devices are running Microsoft’s Windows Mobile operating system and use under a watt of power, meaning they can have days of battery life even though they can run some of the most demanding video and graphics applications.

One of the rumored design wins for Tegra is Microsoft’s upcoming Zune HD digital media player. Neither company has confirmed that, but analysts say they believe the Microsoft product is one of the more important designs in the works. Rayfield said most of the new devices are coming in the fall.

Nvidia’s aim with Tegra is to fill the gap bteween netbooks, or mini laptops, and smart phones. Rivals include Qualcomm’s Snapdragon chip and Intel’s Atom. Nvidia worked on Tegra for five years and announced it about a year ago.

Rayfield said you can listen to music for 25 days on Tegra compared to just five hours on Atom, and 60 hours on Snapdragon. You can watch high-definition video for 10 hours with Tegra, just three hours on Atom, and HD doesn’t run on Snapdragon. You can play the 3-D game Quake at 46 frames per second on Tegra, 17 frames per second on Atom, and 5 frames per second on Snapdragon. He said Tegra can also run Adobe Flash applications while Atom and Snapdragon can’t.

Rayfield said a new version of Tegra will debut next year with four times more performance on a half a watt of power. By 2011, Tegra will have 10 times more performance on a half a watt, he said. He expects the market for mobile Internet devices to be around 25 million units in 2010. Nvidia is also making headway with Ion, its chipset for Intel Atom-based netbooks. The company says 40 Ion projects are under design.

In the long term, Nvidia expects half of its business to come from Tegra, which is virtually nothing right now, said Jen-Hsun Huang, chief executive of Nvidia. He said that computers will be smaller, be available everywhere, and connect to the web. Those trends favor Tegra.

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